Subarcsecond Mid-Infrared Imaging of Dust in the Bipolar Nebula Hen 3-401

We present high-resolution, nearly diffraction-limited narrow- and broadband mid-IR images of bipolar reflection nebula Hen 3-401. The deconvolved images yield a pixel-limited spatial resolution of 0.09", demonstrating the superior imaging quality of the Gemini telescope. The infrared image of Hen 3-401 consists of a prominent core region of size 1" and extended emissions along the walls of the bipolar lobes. We find that the distribution of aromatic infrared band (AIB) emission is different from that of the continuum emission and that the star has undergone multiple ejection of the AIB emission feature carrier at the end stages of its evolution. From the observed temperature gradient in the core, we suggest that the core has a flared disk geometry.

This paper is based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (US), the Particle Physics and Astronomy Research Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina).